1. Field of the Invention
The present invention relates to generating and executing voice enabled web applications within a hypertext markup language (HTML) and hypertext transport protocol (HTTP) framework.
2. Description of the Related Art
The evolution of the public switched telephone network has resulted in a variety of voice applications and services that can be provided to individual subscribers and business subscribers. Such services include voice messaging systems that enable landline or wireless subscribers to record, playback, and forward voice mail messages. However, the ability to provide enhanced services to subscribers of the public switched telephone network is directly affected by the limitations of the public switched telephone network. In particular, the public switched telephone network operates according to a protocol that is specifically designed for the transport of voice signals; hence any modifications necessary to provide enhanced services can only be done by switch vendors that have sufficient know-how of the existing public switched telephone network infrastructure.
An open standards-based Internet protocol (IP) network, such as the World Wide Web, the Internet, or a corporate intranet, provides client-server type application services for clients by enabling the clients to request application services from remote servers using standardized protocols, for example hypertext transport protocol (HTTP). The web server application environment can include web server software, such as Apache-based software available from The Apache Software Foundation, implemented on a computer system attached to the IP network. Web-based applications are composed of HTML pages, logic, and database functions. In addition, the web server may provide logging and monitoring capabilities.
In contrast to the public switched telephone network, the open standards-based IP network has enabled the proliferation of web based applications written by web application developers using ever increasing web development tools. Hence, the ever increasing popularity of web applications and web development tools provides substantial resources for application developers to develop robust web applications in a relatively short time and an economical manner. However, one important distinction between telephony-based applications and web-based applications is that telephony-based applications are state aware, whereas web-based applications are stateless.
In particular, telephony applications are state aware to ensure that prescribed operations between the telephony application servers and the user telephony devices occur in a prescribed sequence. For example, operations such as call processing operations, voicemail operations, call forwarding, etc., require that specific actions occur in a specific sequence to enable the multiple components of the public switched telephone network to complete the prescribed operations.
The web-based applications running in the IP network, however, are state-less and transient in nature, and do not maintain application state because application state requires an interactive communication between the browser and back-end database servers accessed by the browsers via a HTTP-based web server. However, an HTTP server provides asynchronous execution of HTML applications, where the web applications in response to reception of a-specific request in the form of a URL from a client, instantiate a program configured for execution of the specific request, send an HTML web page back to the client, and terminate the program instance that executed the specific request. Storage of application state information in the form of a xe2x80x9ccookiexe2x80x9d is not practical because some users prefer not to enable cookies on their browser, and because the passing of a large amount of state information as would normally be required for voice-type applications between the browser and the web application would substantially reduce the bandwidth available for the client.
Commonly-assigned, copending application Ser. No. 09/480,485, filed Jan. 11, 2000, entitled Application Server Configured for Dynamically Generating Web Pages for Voice Enabled Web Applications, the disclosure of which is incorporated in its entirety herein by reference, discloses an application server that executes a voice-enabled web application by runtime execution of extensible markup language (XML) documents that define the voice-enabled web application to be executed. The application server includes a runtime environment that establishes an efficient, high-speed connection to a web server. The application server, in response to receiving a user request from a user, accesses a selected XML page that defines at least a part of the voice application to be executed for the user. The XML page may describe any one of a user interface such as dynamic generation of a menu of options or a prompt for a password, an application logic operation, or a function capability such as generating a function call to an external resource. The application server then parses the XML page, and executes the operation described by the XML page, for example dynamically generating an HTML page having voice application control content, or fetching another XML page to continue application processing. In addition, the application server may access an XML page that stores application state information, enabling the application server to be state-aware relative to the user interaction. Hence, the XML page, which can be written using a conventional editor or word processor, defines the application to be executed by the application server within the runtime environment, enabling voice enabled web applications to be generated and executed without the necessity of programming language environments.
Hence, web programmers can write voice-enabled web applications, using the teachings of the above-incorporated application Ser. No. 09/480,485, by writing XML pages that specify respective voice application operations to be performed. The XML documents have a distinct feature of having tags that allow a web browser (or other software) to identify information as being a specific kind or type of information. In particular, commonly-assigned, copending application Ser. No. 09/501,516, filed Feb. 1, 2000 entitled Arrangement for Defining and Processing Voice Enabled Web Applications Using Extensible Markup Language Documents, the disclosure of which is incorporated in its entirety herein by reference, discloses an arrangement for defining a voice-enabled web application using extensible markup language (XML) documents that define the voice application operations to be performed within the voice application. Each voice application operation can be defined as any one of a user interface operation, a logic operation, or a function operation. Each XML document includes XML tags that specify the user interface operation, the logic operation and/or the function operation to be performed within a corresponding voice application operation, the XML tags being based on prescribed rule sets that specify the executable functions to be performed by the application runtime environment. Each XML document may also reference another XML document to be executed based on the relative position of the XML document within the sequence of voice application operations to be performed. The XML documents are stored for execution of the voice application by an application server in an application runtime environment.
Hence, the XML document described in the above-incorporated application Ser. No. 09/501,516, which can be written using a conventional editor or word processor,.defines the application to be executed by the application server within the runtime environment, enabling voice enabled web applications to be generated and executed without the necessity of programming language environments.
Conventional application development environments maintain a substantial distinction between application use and application development. In particular, most applications are developed either by writing source code using a conventional programming language and compiling the written code into executable format, or using a stand-alone development tool that generates the required application. After the application has been developed into executable code, the executable code is then executed by a processing system for testing prior to actual use by subscribers. The distinction between application use and application development hinders efficiency in application development, since a developer is unable to obtain immediate feedback from adding any changes to an application. Hence, an application developer having discovered an undesirable result in the application during execution typically needs to retrace the executable code to locate the cause of the undesirable result, slowing the application development process.
There is a need for an arrangement that enables a user to develop voice enabled web applications using a browser, where the user can concurrently generate new voice application operations and test the voice application operations executed by an application server.
There also is a need for an arrangement that enables voice applications to be defined using extensible markup language (XML) documents in a manner that provides flexible control of the voice applications. In particular, there is a need for an arrangement that enables the modification of existing application parameters of a voice-enabled web application, or the addition of new application parameters, without affecting unmodified application parameters.
These and other needs are attained by the present invention, where an application server that executes a voice application defined by XML documents dynamically generates an HTML form specifying selected application parameters from an XML document executable by the voice application. The HTML form is supplied to a browser, enabling a user of the browser to input or modify application parameters for the corresponding XML document into the form. The application server, upon receiving the form from the web browser, inserts the input application parameters into the XML document, and stores the application document for execution. Since voice applications are executed by the application server based on runtime parsing of the XML document, a user can concurrently use the HTML form to create or modify an XML document, post the HTML to the application server, and then execute the XML document to validate the inputs supplied to the HTML form. Hence, a user can easily generate XML documents and verify the corresponding voice application operation using a forms-based application development methodology.
One aspect of the present invention provides a method in an application server for developing an executable voice application. The method includes generating a hypertext markup language (HTML) document that specifies a form having at least one entry field for specifying an application parameter, and sending the HTML document to a web browser. The method also includes receiving the form from the web browser, the received form having an input application parameter in the entry field, inserting the input application parameter into an extensible markup language (XML) document configured for defining an operation of the executable voice application, and storing the XML document for execution by the application server. Generation of an HTML document that specifies a form for entry of application parameters enables an application developer to use an HTML forms representation of the application defining XML documents. Hence, an application developer can develop an XML-based voice web application without the necessity of any experience in writing code in existing programming languages. Moreover, the application developer can use a browser to create or modify a voice enabled web application; consequently, the request-based interaction between the browser and the application server enables an application developer to create or modify an XML document, and then cause the application server to execute the XML document in the same browser window.
Another aspect of the present invention provides a method in a browser for developing an executable voice application. The method includes sending a first request to a web server according to hypertext transport protocol (HTTP) for a first hypertext markup language (HTML)-based web page having a form with at least one entry field for inputting an application parameter, receiving and displaying the form, and posting the form, including an input application parameter in the entry field that is input by a user, to a prescribed uniform resource locator (URL). The method also includes sending a second request to the web server for execution of the executable voice application based on the posted form, and receiving a second HTML-based web page having voice application content based on the posted form. The posting of the form having the input application parameter enables a user of the browser to supply application parameters to an application server to define voice application operations in an XML document. Moreover, the sending of a second request for execution of the executable voice application based on the posted form and reception of the corresponding second HTML-based web page enables a user to personalize voice application operations within a voice enabled web application, and then test the input changes by obtaining the results of execution of the voice enabled web application by the application server.
Still another aspect of the present invention provides a system configured for developing an executable voice application. The system includes a computer-based server and a storage medium. The computer-based server has an application runtime environment configured for generating for a browser a first hypertext markup language (HTML) document that specifies a form having at least one entry field for specifying an application parameter. The application runtime environment, in response to reception from the browser of a first HTTP request specifying the application parameter, inserts the application parameter specified by the first HTTP request into an XML document. The application runtime environment also selectively executes the XML document having the application parameter specified by the first HTTP request in response to a second HTTP request. The storage medium is configured for storing the XML document created or modified by the computer-based server.
Additional advantages and novel features of the invention will be set forth in part in the description which follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The advantages of the present invention may be realized and attained by means of instrumentalities and combinations particularly pointed out in the appended claims.